1. Field of the Invention
The present invention relates to data mining and, more particularly, to a method of visually detecting relationships between values of related goals and variables of a plurality of design points of a circuit.
2. Description of Related Art
Heretofore, methods of generating analog circuit designs were based on synthesis programs implemented on a computer. Each synthesis program generates a set of design points for a circuit based upon design variables, design goals and constraints for the circuits. More specifically, each design point is determined from a common set of variables and a common set of goals for the circuit, with each design point having at least one variable or goal different from each other design point.
Each design point also has a cost or cost value associated therewith. The cost of each design point represents the quality of the design point with respect to a given set of goals, each having a target value and a constraint associated therewith. Design points where the goals better satisfy their design constraints have a lower cost associated therewith.
Depending on the type of circuit design and the user specified set of information that is input into the synthesis program, the number of design variables and goals vary from several hundred to several thousand. After a synthesis run is complete, a single combination of design variable values and design goal values, i.e., a single design point, is selected. This design point is used as a starting point for an implementation of the circuit on a semiconductor chip. In another application, a set of design points is generated by sampling in the vicinity of a chosen design point. This is typical when the existing “best” design needs to be improved or when it is desired to better understand local variations in the design variables and the design goals.
Given the large size of the set of design points and the number of variables and goals, it is difficult for a human designer to understand the advantages or disadvantages of selecting a particular design point. It is also difficult to focus on a desired subset of design points by using conventional inspection techniques, such as examining the numerical/textual output of the synthesis program or examining design points one by one. Even when using advanced database querying techniques, significant challenges remain in analyzing this large data set with the large number of design variables and design goals.
Accordingly, it is desirable to overcome the above problems and others by providing a visual data mining technique that enables analysis of the generated set of design points to provide an easy and fast understanding of important properties of the generated designs; fast, intuitive and easy selection of subsets of design points, or a single design point, with desired properties based on the analysis; and which significantly reduces the time for analysis of the design space and the decision on which design point to choose for practical implementation.